U.S. Pat. application Ser. No. 398,974, now U.S. Pat. Ser. No. 3,853,626 filed Sept. 20, 1973 in the names of Daniels et al and assigned to the assignee of the present invention, discloses a continous, in-line process for making a lead-acid storage battery grid having a current-collecting header of unexpanded strip and a reticulated portion expanded, guillotine-style, from the strip into a plurality of paste-retaining cells bounded by skeletal elements and nodes formed during expansion. This invention is an improvement to the Daniels et al method as it relates to positive grids made from Pb-Ca alloys, and the said Daniels et al patent application is intended to be incorporated herein by reference. Briefly, in the Daniels et al method, a ribbon or strip of lead (e.g., Pb-Ca alloy) is fed into a continous, in-line, guillotine-type, dual expansion machine and therein expanded along its longitudinal edges into two reticulated portions extending laterally from a central unexpanded portion from which headers and lugs are subsequently formed. The expanded strip has a V-shape or gull-winged configuration when viewed from its end, the wings of which are subsequently folded down as by plow and roller means so as to be in substantially the same plane as the unexpanded portion. The reticulated portions are subsequently uniformly stretched in a direction perpendicular to the central unexpanded portion by cooperating embossed and mating forming rolls. Finally, the reticulated portion is rolled so as to twist and flatten the nodes joining skeletal elements.
One of the advantages of such a process is that it can be coupled directly to the output of a continous strip casting machine such as the one described by R. D. Semmens in the article entitled "The Continuous Casting of Lead Sheet by the D.M. Process", Journal of the Australian Institute of Metals, Vol. 10, No. 1, Feb. 1965, pp. 40 - 44. Such a melt-to-plate scheme is illustrated in FIGS. 8 and 9 hereof and permits the continuous production of battery plates without any intermediate handling of individual grids. Such a melt-to-plate scheme has proven to be particularly useful in the manufacture of grids destined for negative plates as the negative plates are not subjected to the same corrosive attack and active materials growth seen by positive plates.